Dispensing of fluids

ABSTRACT

A container for dispensing fluid under pressure, the container have a top and a base with a floor raised above the base by a downwardly depending skirt, a high pressure canister being positioned under the floor of the container within the skirt and having a regulator which is adapted to extend through the floor and into the container, whereby the regulator causes release of gas from the high pressure canister when the internal pressure in the container falls below a predetermined level.

FIELD OF THE INVENTION

This invention relates to the dispensing of fluids and, in particular,relates to the dispensing of beer under pressure.

BACKGROUND OF THE INVENTION

Beer drinkers are particularly fond of beer which is dispensed underpressure from a barrel. In commercial facilities, the beer is stored inlarge barrels and then dispensed under pressure from a beer tap. This isknown as draught beer and is particularly popular the world over.

Attempts have been made to provide smaller barrels for domestic use.These barrels can vary between 5 L and 100 L and are usually pressurisedto ensure the beer is dispensed in the same manner as draught beer isdispensed in commercial establishments.

A problem with the domestic style of barrel is encountered in ensuringthe beer is dispensed consistently at the required pressure. There is atendency for the beer to be over pressurised at first usage and, then asthe pressure within the barrel drops, the beer becomes either flat or isdifficult to dispense due to a loss of pressure. It has been proposed toplace, within the beer barrel, boosters in the form of small, highlypressurised canisters that release a boost of gas, usually nitrogen orcarbon dioxide, into the beer as the pressure within the barrel drops.It is these issues that have brought about the present invention.

SUMMARY OF THE INVENTION

According to one aspect of the present invention there is provided acontainer for dispensing fluid under pressure, the container having atop and a base having a raised floor supported by a downwardly dependingskirt, a dispensing tap located in the container, the floor of thecontainer having an aperture, a high pressure canister being profiled tofit within the skirt under the floor of the container, the canisterhaving projecting therefrom a regulator which is adapted to fit into theaperture with the regulator extending into the container, the regulatorhaving a primer whereby in use when the container is filled with fluidand the interior of the container pressurised the regulator is primed sothat as the pressure in the container drops as the fluid is dispensedthe regulator activates a valve in the canister to release gas underpressure into the container to elevate the pressure within the containerto maintain a substantially constant pressure.

According to another aspect of the present invention there is provided acontainer for dispensing fluid under pressure, the container having atop and a base with a floor raised above the base by a downwardlydepending skirt, a high pressure canister being positioned under thefloor of the container within the skirt and having a regulator that isadapted to extend through the floor and into the container.

According to one aspect of the present invention there is provided amethod for preparing a container for dispensing of fluid undersubstantially constant pressure, comprising attaching a pressure controldevice to the underside of the exterior of the container, the pressurecontrol device having a regulator adapted to extend through the floor ofthe container into the interior of the container, the regulatorincluding a primer whereby the method comprises securing the pressurecontrol device to the container, filling the container with fluid,pressurising the container to a pressure slightly above the operatingpressure via the dispensing tap, the pressure control device eitherbeing subsequently pressurised to an excess pressure or being suppliedpre-pressurised to the excess pressure.

DESCRIPTION OF THE DRAWINGS

An embodiment of the present invention will now be described by way ofexample only with reference to the accompanying drawings in which:

FIG. 1 is a side elevational view of a container for dispensing beer;

FIG. 2 is a cross sectional area taken on the lines AA of FIG. 1;

FIG. 3 is an enlarged view of the cross section of the base of thecontainer illustrating a pressure booster and regulator primed for use;and

FIG. 4 is an enlarged cross sectional view of the regulator whenactivated to release pressurised gas from the booster.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The beer barrel 10 illustrated in the accompanying drawings isconstructed of metal to assume a cylindrical shape with a top 11 andbase structure 12. The actual floor 13 of the barrel 10 is raised abovethe base 12 of the barrel and is supported by an annular skirt 14 thatdefines a space 15 between the floor 13 of the barrel and the base ofthe skirt 14.

This space 15 is utilised to house a canister 20 which can bepressurised with gas, usually a mixture of nitrogen and carbon dioxide,to pressures in excess of 500 psi. The canister 20 is toroidal in shapeand is designed to fit within the space defined by the skirt at the baseof the barrel. As shown in FIG. 3, the toroidal canister has inwardlydished top and bottom walls 21 and 22 and has a central aperture 23 thatsupports a plug 30 that has a central throughway 31, an enlarged upperflange 32 that is welded to the upper surface of the top wall 21 of thecanister 20 and a lower flange 33 which projects past the bottom wall 22of the canister 20 to terminate approximately level with the base 12 ofthe barrel 10.

The throughway 31 is stepped to define a wide opening 36, a threadedportion 37 and an unthreaded passage 35. The opening 36 is closed by aremovable end cap 39. A valve body 40 is screwed into the threadedpassageway 37 and located in a sealed engagement with the plug 30 via anO-ring 41. The valve body 40 has a one-way valve including a valvemember 42 located by a retainer 43 against a coil spring (not shown).The end 45 of the valve member 42 projects into a conical space 43defined within the valve body 40 and the valve member 42 includes a head47 which seats against an internal bore 48 of the valve member via anO-ring 49. The one-way valve is used to pressurise the canister 20 andthe plug 30 has at least one aperture 46 that communicates with theinterior of the canister.

The floor 13 of the beer barrel 10 has a centrally positioned aperture16 and a circular mounting boss 17 with a central partially threadedaperture 18 is welded to the interior of the floor 13 of the barrel toextend across the aperture 16.

The upper flange 32 of the plug 30 has an upwardly and outwardlyprojecting spigot 38 which is externally threaded to screw into the boss17 welded to the floor 13 of the barrel 10. The spigot 38 in turn has aninternally threaded aperture 39 that accommodates a screw threadedspigot 51 formed on the end of a second plug 60 that forms the base ofthe regulator 50 which extends into the barrel as shown in FIG. 2.

In this manner, the centrally located plug 30 welded to the canister 20is screw threaded through the floor 13 of the beer barrel in the boss 17with the regulator 50 extending into the interior of the beer barrel.This allows the canister 20 to be protected by the downwardly dependingskirt 14 on the beer barrel 10 and the regulator 50 to be firmly locatedwithin the base of the beer barrel to communicate with the interior ofthe beer barrel so that, when activated, the high pressure within thecanister 20 can be released into the beer barrel.

In use, the barrel 10 can be inverted and filled with beer through theaperture 16 in the floor 13 of the barrel 10 and then the canister 20and regulator 50 are screwed into the floor 13 of the barrel.Alternatively, the canister 20 and regulator 50 can be screwed into thefloor 13 of the barrel 10 and then the barrel is filled with beer from adispensing tap (not shown) at the top 11 of the barrel 10. The canister20 can be pressurised to the desired pressure of approximately 500 psieither prior to delivery or can be pressurised through the one-way valve40 after being positioned in the base of the barrel 10.

Once the barrel 10 is full of beer, it is then pressurised via thedispensing tap to a pressure of approximately 20 psi.

The regulator 50 is of the kind disclosed in U.S. Pat. No. 7,021,559,the disclosure of which is incorporated herein by reference.

The regulator 50 essentially comprises a one-way valve housed in thesecond plug 60. A cap 70 is secured to the plug and includes twopressure chambers 71, 72 and a piston 73. A primer 80 in the form of asyringe body 81 is secured to the top of the cap 70.

The second plug 60 has a central throughway 61 which locates a one-wayvalve 62 in the same manner as the one-way valve 40 in the base of thecanister 20. The one-way valve comprises a valve member 63 having a head64 that seals against a valve seat 65, a retainer 66 enclosing a coilspring (not shown) about the valve stem 67 and the end of the valve stem67 is connected to the piston 73 which is axially slidable within acylinder defined by a the interior of the cap 70 which is secured to theexterior of the plug 60 and sealed thereon by welding or adhesive.

The cap 70 also includes a central hollow projection 74 defining achamber 76 which houses a flexible chamber seal 75. The space betweenthe underside of the piston 73 and the one-way valve 62 is incommunication with the interior of the barrel 10 and defines the firstpressure chamber 71 and the space between the other side of the piston73 and the cup seal 75 defines the second pressure chamber 72 orexpandable chamber. Projecting axially from the top of the secondchamber 72 is the syringe body 81 which includes a piston 82 with adownward projection 83 constituting the primer 80. The chamber seal 75is annular with a peripheral lip 77 supported by an annular rib 78 withthe peripheral lip 77 and annular rib 78 bearing against the wall of thechamber 76. The expandable chamber 72 is on one side of the chamber seal75.

When the barrel 10 is pressurised, the piston 82 in the syringe body 81is forced down to force gas past the chamber seal 75 into the secondchamber 72. The design of the chamber seal 75 is such that the pressurewithin the second chamber 72 on one side of the piston 73 is about 3 psiless than the pressure in the first chamber 71 on the other side of thepiston 73 which equates to the internal pressure of the barrel 10. Asthe contents of the barrel are released and the internal pressure drops,eventually the pressure in the first chamber 71 (about 17 psi) becomesgreater than the internal pressure of the barrel 10 causing the piston73 to be displaced downwardly to open the one-way valve 62 which causesrelease of the high pressure gas within the canister 20 to recharge thebarrel 10. In this way, the syringe piston 82 primes the cup seal 75 foruse at start up to be operable once the barrel has been charged. As thepressure in the barrel 10 drops below 17 psi, the one-way valve isactivated causing the barrel to be recharged from the high pressure gascontained in the canister 20 in the base of the barrel.

An important design consideration with the barrel described above is itspotential for reuse. The barrel, the pressurised canister and the plugwhich screws into the base of the barrel are all reusable. The onlydisposable and redundant component is the regulator and primer.

1. A container for dispensing fluid under pressure, the container havinga top and a base with a floor raised above the base by a downwardlydepending skirt, a high pressure canister being positioned under thefloor of the container within the skirt and having a regulator, which isadapted to extend through the floor and into the container, whereby theregulator causes release of gas from the high pressure canister when theinternal pressure in the container falls below a predetermined level. 2.The container of claim 1 wherein the regulator includes a one way valvethat is driven to open to release high pressure gas from the canisterwhen the pressure in the container drops below a predetermined level. 3.The container of claim 2 wherein the one way valve is driven by drivemeans actuatable by pressure within an expandable chamber sealed by achamber seal whereby when the pressure within the container drops belowthe pressure in the expandable chamber the drive means opens the one wayvalve.
 4. The container of claim 3 wherein the regulator includes aprimer to prime the expandable chamber to a pressure slightly below thepressure in the container.
 5. The container of claim 4, wherein theprimer comprises a piston displaceable within a cylinder by pressurewithin the container to engage the chamber seal and pressurize theexpandable chamber.
 6. The container of claim 3 wherein the chamber sealis annular with a peripheral lip supported by an annular rib with thelip and rib bearing against a wall of the chamber.
 7. The container ofclaim 1, wherein the canister is adapted to screw into an aperture inthe base of the container with a regulator extending through theaperture.
 8. The container of claim 1, having a dispensing tap to allowthe fluid to be dispensed under pressure.
 9. The container of claim 1,wherein the canister has a one way valve to facilitate the filling ofthe canister at high pressure.
 10. The container of claim 1, wherein thecontainer is cylindrical and the canister is toroidal.
 11. A containerfor dispensing fluid under pressure, the container having a top and abase having a raised floor supported by a downwardly depending skirt, adispensing tap located in the container, the floor of the containerhaving an aperture, a high pressure canister being profiled to fitwithin the skirt under the floor of the container, the canister havingprojecting therefrom a regulator, which is adapted to fit into theaperture with the regulator extending into the container, the regulatorhaving a primer whereby in use when the container is filled with fluidand the interior of the container is pressurized and the regulator isprimed so that as the pressure in the container drops as the fluid isdispensed the regulator activates a valve in the canister to release gasunder pressure into the container to elevate the pressure within thecontainer to maintain a substantially constant pressure.
 12. A methodfor preparing a container for dispensing fluid under substantiallyconstant pressure from a dispensing tap, comprising attaching a pressurecontrol device containing gas at high pressure to the underside of theexterior of the container, the pressure control device having aregulator adapted to extend through the floor of the container into theinterior of the container, the regulator including a primer; filling thecontainer with fluid; and pressurizing the container to a pressureslightly above the operating pressure via the dispensing tap to primethe regulator.
 13. The method of claim 12 wherein the pressure controldevice may be pressurized in situ via a one way valve or suppliedpre-pressurized.